Road grader



Jan. 8, 1929.

C. A. GUSTAFSON ROAD GRADER Filed June 25, 1927 5.Sheets-Sheet l #uuml-9i [NMS/WOR AR/.Avsm/-Sm/ BWM WM Jan. 8, 1929. 1,698,435

- c. A. GUsTAFso-N y r ROAD GRADER Filed June 23, 1927 3 Sheets-Sheet 2INVNTOR ARL A. usTAFso/v By@ www Jan.' 8, 1929.

C. A. GUSTAFSON ROAD GRADER Filed June 23, 1927 in the worms.

i i Ea? CARL A. GUSTAFSON, 0F MINNEAIPOLIS, MINNESOTA, AVSSIGNDR TORUSSELL-GRADER MANUFACTURING COMPANY, 0F MINNEAPOLIS, MINNESOTA, ACORPORATION 0F MINNESOTA.

:Roan GRADE'R.

Application filed June 23, 1927. Serial No. 200,882.

This invention relates to new and useful improvements in road graders,generally,

and more particularly to such graders coniprising a main frame having ascraper blade movably mounted therebeneath, and, a-nobject of theinvention is to provide in connection with such a machine, means fortaking up al1 play or looseness in the joints between the scraper bladeand the operating mechanism therefor, thus preventing or minimizing thechattering of the blade, when engaged with a hard ground surface.

A further object of the invention is to provideV a road grader, havingcrank shafts mounted thereon for -vertically ad'usting the scra erblade, which are opera le by means o worm-and-gear mechanisms, and thecrank-shaft supporting bearings adjacent to the worm gears, havingeccentric means for relatively7 adjusting the gears with respect to theworms for the purpose of taking up play therebetween and, further, meansare provided for taking up end play A further object ,is to provide aroad grader having a crank-shaft mounted thereon" fory raising andlowering the scraper blade, and the crank end of the shaft beingsupported in a bearing having means for taking up play therein, suchmeans comprising a semi-annular cap or collar iitted over the shaftandsecured in adjusted position by means of a lock screw.

A further object is to provide a grader having a draft frame mountedtherebe'neath and pivotally connected at one end to the grader frame,and a circular blade-supporting frame being adjustablfy connected to thea road grader, adjustable means for taking up play or looseness in thejoints in the operating mechanism between the scra er blade and thehand-wheel, usually provi .ed

from the following description and accom- Y panying'drawings and will bepointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structuredesigned to carry out the various objects of the invent-ion, but it isto be understood that the invention is not confined to thefexactfeatures shown, as various changes may be made within the scope of theclaims which follow.

ln the accompanying drawings forming part of this specification:

Figure 1 is a view in side elevation, show ing a conventional type ofroad grader with the invention applied thereto;

Figure 2 is an enlarged detailed sectional view showing the connectionbetween th'e scraper blade supporting frame and the main frame of thegrader;

Figure 3 is an enlarged detailed sectional view on the line 3-3 ofFigure 1;

Figure 4 is a detailed sectional view o the line 4--4 of Figure 5;

Figure 5 is an enlarged detailed sectional view on the line 5-5 ofFigure 4, showing the means provided for taking up play in the bearing;

Figure 6 is an enlarged detailed sectional view, showing theworm-and-gear mechanism for rotating the blade-operating crank shaft;

Figure 7 is a detailed sectional view on the line 7-7 of Figure 6,showing the eccentric for relatively adjusting the position of the worm`gear with respect to the worin; Figure 8 is a sectional plan view onthe line 8 8 of Figure 6, showing the take up means between the 'Wormsupporting bearings;

Figure 9 is an enlarged detailed sectional view of the eccentric`,removed fromthe shaft Figure 10 is a detailed plan view showfVv ingthe connection between the auxiliary frame and the circular bladesupporting frame; and i Figure 11 is a detailed sectional view on`blade-supporting frame 6 connection with the forward end of the graderin the usual manner. The circular is rotatably mounted upon the rear endof the draft frame 5 and has the scraper blade 7 attached thereto, asshown in Figure 1.

In the operation ofa road grader, it is essential that the scraper blade7 is retained substantially rigid with respect to the main frame 2 ofthe grader, when engaged with the ground surface. 1n other words, it isessential that all of the joints in the connections between the bladeand the grader frame are substantially free from play or looseness, inorder that the blade will be pre-` vented from chattering when engagedwith a hard road surface. Such elimination of vblade-chattering is ofutmost importance because a smooth road surface cannot be obtained witha chattering blade, and an im` portant feature of this invention is toprovide means for thus taking up all play and looseness in Atheconnections between the rotatably connected with the draft frame 5,

the rear end of which has a transversely disposed cross member 9 securedthereto, and

` to the terminals of which the lower ends of connecting rods 11 arepivotally connected, the u per ends of which are similarly connecte tocrank arms 12, secured to a pair of crank shafts 13 mounted in bearings14 and 15, secured to the main frame 2. Each crank shaft 13 has a 'wormgear 16 secured'thereto which meshes with. the worm 17, having shaftextensions 18 and 19 mounted respectively in bearings 21 and 22. Thehand wheels 8 are terminally secured to the shaft extensions 18 as shownin Figure 8, whereby the worms may 'be operated independently ofeachother, as is common practice.

Means are provided for taking up play between the intermeshing teeth ofthe worm wheel 16 and the worm 17, and consists of an eccentric bearingsleeve 23 being rotatablymounted i'n each bearing 15, as shown in Figure7. Each bearing sleeve 23 has a flange 24 provided at one end thereof,in which is an arcuately formed slot 25, as shown in Figures 6 and 9. Astud 26 traverses each slot 25 -and is-secured to the end of thecomplementary bearing or hub 15. The studs are terminally threaded toreceive nuts 27, which function to lock the eccentric sleeves 23 intheir adjusted positions. Referring to Figures 6 and 7, it will be notedthat when the sleeve 23 is rotated in the hub 15, the crank shaft 13will be moved towards or closer to the worm wheel 17, thus moving theteeth of the worm and gear into closer intermeshing relation with theresultant elimination of play therebetween.

rhe bearing 22, supporting the shaft extension 19 of the worm wheel 17,is adjustably secured to its supporting bracket 28 by means of bolts 29and slotted apertures 31, shown in dotted lines in Figures 6 and 8. Thebearings 21 and 22 are each provided with an outwardly extending lug 32which are apertured to receive a tie bolt 33, as shown in Figure 8. Bymeans of this tie bolt and the adjustment afforded the bearing 22, endplay y.may be taken up between the two bearings to prevent relativeaxial movement of the worm 17.

The bearing brackets 14 at the forward end of the crank shafts 13 arealso provided with means for taking up play therein, caused by wear andso on. Referring to Figure 5, it will be noted, that each bearingbracket 14 has a semi-annular bearing cap or sleeve 34 which cooperateswith the n bracket 14 to provide a bearing for the shaft. Each bracket14 has an enlarged semi-circular opening 35 adapted to receive thebearing caps 34, as shown in Figures 3 and 5. Shimsl 36 are interposedbetween the lower bearing faces 37 and the adjacent faces of..Y the cap34 to. accurately space the cap from the faces 37 of the bearing bracket14. A set screw 38 is received in threaded engagement with the upperportion of each Ybracket 14 and terminally engages its complementarycap' 34 to lock the latter in adjusted position. An oil pipe 39 issecured to each cap 34 and to the outer end of which may be secured anoil cup, whereby oil may be introduced into the bearing.

Another feature of the invention resides in the means provided fortaking up play between the circular blade-supporting frame 6 and thedraft frame5. Such means is shown in detail in Figures 10 and 11.Referring more particularly to Figure 10, it will be noted that thedraft bars 5 are secured to the transverse member 9 by means of brackets41, each having an outwardly projecting tongue or flange 42 positionedbeneath the inner horizontal web 43 of the circular frame 6, which itwill be noted, by reference to Figure 11, is of T-shaped cross section.Each bracket 41 is further provided ally adjusted so as to permitthecirculary frame to be adjusted or rotated with respect yto the draft.bars of frame 5, and if the'road surface is found to be hard and theblade has a tendency to chatter, the 'clamping blocks 4G may be clampedagainst the web 43 to securely lock the circular frame to the draftframe, thus positively preventing any play therebetween.l

From the foregoing, therefore, it wil readily be understood that by theemployment of the various play vtake-up devices interposed in theconnections between 4the scraper blade and the main frame and also thehand wheels 8, that all play or looseness in the joints can be taken upso that the blade, when engaged with the road surface will have, ineffect., a rigid connection with the main frame 2 of the grader; Thetakeup means featured in lthis invention-have therefore been found veryessential in the operation of road lgraders or road working machines,employing.,r a `ground working blade, as, by their employment, the bladewill be positively held against play, thus producing a sl'nooth anduniform cut- 1n the road surface. The combination of the Varloas take-upmeans, as set forth in this in# vention, are therefore essential to thesuccessful operation of the road grader, as they cooperate With oneanother to obtain one result, namely, thatof eliminatinga'll loosenessor slack in the connections between the scraper blade and its operatingmechanism.

I claim as my invention:

.1. A road grader comprising. in combination, a main frame, a draftframe pivotally connectedl thereto, a scraper supporting frame, a guidebracket secured to the draft l frame and adapted to receive and guidesaid scraper frame, a socket in the bracket, a block mountedl in saidsocket, and meansfor scraper supporting frame to take up playltherebetween.

, moving said block into engagement with said 2. A road gradercomprising a main frame having a draft frame connected therewith, guidebrackets secured to the rear portion of said draft frame, al scraperframe adjustably mounted in said guide brackets, a socket in eachbracket, a block mounted in each socket, means for moving said blocksinto engagement with said scraper frame, `operating mechanism connectedwith said draft frame for raising and lowering said draft frame and saidscraper frame, and non-yieldable take-up means in the connectionsbetween lsaid draft frame and said operating means.

blocks into. engagement with said scraper .I

frame to take up-play.. v l

In witness'- whereof, I have hereunto set 'my hand this 4th day` of May,1927i CARL A. easTArsoN.V

